2D lighting to effect sprites based on y position for top down games

Is it possible meanwhile to realise a similar effect to this with the build in lighting of Unity:



Meaning: Objects that are lower on the y axis (In front) of the light source appear dark, despite both trees have the same distance to the light source. (Image From Article: https://www.gamasutra.com/blogs/Svy..._Keeper_How_the_graphics_effects_are_made.php )

Is this something you can achieve with shaders or shadergraph?

 

Looks like something you'd want to use shadow casters for. Best to look into them. You can make your own custom lighting shader, but would probably be a pain. That said, having tinkered with shadow casters, the look they give might not work for you so you might have to.

 

Yeah Shadowcasters is not a solution. I already assumed that it should be possible to modify the Unity shader in a way to get this result - are there any good tutorials on shaders?

 

You might want to first examine how lighting works in the 2D Renderer. In particular check out the file RendererLighting.cs (search Project in Packages). There's essentially a 2-step process: lights written to RenderTexure then lit sprites sample that RenderTexure. This has the advantage that lit sprites don't check themselves against every light (more lights & sprites therefore scale better), but the disadvantage that you don't have positional information about the lights.

 

Interseting, but how does normal mapping work in that case, as you'd need the direction of the light for the sprites to display normal mapping properly?

 

The light's shader considers that as it renders onto the normals render texture. At least that's my understanding. Haven't looked at that much. See Universal RP > Shaders > 2D > Light 2D Point Volumetric

 

you wont achieve what is happening in this image through out of the box means

reproducing this effect will require a large amount of trickery with invisible 3d models shaders and normal mapping, this is not something that you can drag 1 light into a scene and it works like this

 

I believe you want to use normal maps to achieve this.